Accuracy of Fecal Immunochemical Tests for Detecting Advanced Colorectal Neoplasia at Surveillance Colonoscopy

Q: What patient groups were evaluated for FIT accuracy in this surveillance setting?

Patients were categorized by previous colonoscopy findings into low-, intermediate-, or high-risk polyp groups, and analyses focused on those with nonadvanced prior lesions.

Q: How did the study compare FIT cutoffs for detecting advanced colorectal neoplasia?

It compared an optimal quantitative cutoff identified by the Youden index against the standard cutoff of 100 ng/mL, using diagnostic performance metrics.

Q: What did serial FIT testing contribute to cumulative detection?

Cumulative sensitivity across three rounds was higher at the optimal cutoff (73.4%) than at the standard cutoff (37.1%), while specificity decreased at the lower optimal cutoff.

Sep 23, 2026

Uploaded by Jordan Avery

US guidelines recommend surveillance colonoscopy after polyp removal, but stool testing may offer a more efficient, acceptable strategy for patients with nonadvanced lesions. Exploratory analyses assessed the diagnostic accuracy of quantitative fecal immunochemical testing (FIT) for detecting advanced colorectal neoplasia in patients undergoing surveillance colonoscopy. Participants were classified by prior colonoscopy risk, and performance was compared at an optimal Youden cutoff versus a standard 100 ng/mL cutoff, including cumulative sensitivity and specificity across serial FIT rounds.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages9

Reading Time23 min

AccessFree to download

Introduction

Methods

Results

Discussion

Keywords

ARTICLE 1 | INTRODUCTION: US guidelines recommend surveillance colonoscopy after polyp removal, but stool testing may offera more efficient, acceptable strategy for patients with nonadvanced lesions. We conducted exploratory analyses to evaluate the diagnostic accuracy of quantitative fecal immunochemical testing(FIT) results to diagnose advanced colorectal neoplasia in patients undergoing surveillance colonoscopy.
METHODS: We classified patients by previous colonoscopy findings as having low, intermediate, or high risk polyps. We compared the diagnostic performance for detecting advanced colorectal neoplasia at an optimal cutoff identified by the Youden index vs the standard cutoff of 100 ng/mL. We also estimated cumulative sensitivity and specificity for serial FIT testing in patients with nonadvanced findings.
RESULTS: Among the 449 participants (mean 6 SD age 65.4 6 7.1, 53.2% women, and 92.7% White), the median interval between colonoscopies was 5.0 years(IQR3.5,5.6);adequate or better bowel prep was achieved in 89.3%, and cecal intubation in 98.4% . We detected 55 advanced precancerous lesions, but no cancers. For patients with previous nonadvanced lesions (n 5 378), the optimal cutoff was 26ng/mL. Compared with the standard cutoff, the optimal cutoff increased sensitivity(14.3%–35.7%, P< 0.01)but reduced specificity(95.5%–79.2%, P< 0.01). Estimated cumulative sensitivity across 3 rounds of FIT testing was 73.4% at the optimal cutoff vs 37.1% with the standard cutoff.
DISCUSSION: Lowering the FIT hemoglobin cutoff markedly improved sensitivity for detecting advanced precancerous lesions in patients without previous advanced polyps. Serial testing could further enhance detection. FIT-based surveillance should be further evaluated as a potential strategy to prioritize, delay, or replace colonoscopy.
KEYWORDS: sensitivity and specificity; colorectal neoplasms; surveillance; fecal immunochemical test; colonoscopy
ABBREVIATIONS:ACN, Advanced colorectal neoplasia;APL, Advanced precancerous lesions;BMI, Body mass index;COOP, Colonoscopy vs. Stool Testing in Older Persons; FDA, Food and Drug Administration; FIT, Fecal immunochemical testing; g, Gram; Hb, Hemoglobin; mL, Milliliter; ng, Nanogram; OC, Occult blood; QR, Interquartile range; ROC, Receiver-operating characteristic; SD, Standard deviation; USMSTF, United States Multi-Society Task Force | | | --- | --- | | Clinical and Translational Gastroenterology 2026;17:e00997. [https://doi.org/10.14309/ctg.0000000000000997](https://doi.org/10.14309/ctg.0000000000000997) | | | INTRODUCTION
The US Multi-Society Task Force (USMSTF) recommends colonoscopy as the preferred surveillance strategy after polypectomy (1). The surveillance interval depends on the histology, size, and number of polyps found on the previous colonoscopy. | However, the USMSTF noted the limited evidence demonstrating that polypectomy reduces the risk of incident and fatal colorectal cancer, particularly in the absence of high-risk features. Accordingly, the guideline now recommends longer surveillance intervals for individuals with lower risk polyps. | Accuracy of Fecal Immunochemical Tests for Detecting Advanced Colorectal Neoplasia at Surveillance Colonoscopy Richard M. Hoffman, MD, MPH1 , Yinghui Xu, MS2 , Seth D. Crockett, MD, MPH, FACG3 ,4 , Jeanette M. Daly, RN, PhD2 , Gloria D. Coronado, PhD5 and Barcey T. Levy, MD, PhD6 COLON 1University of Iowa Carver College of Medicine, and Holden Comprehensive Cancer Center, Iowa City, Iowa, USA; 2University of Iowa Carver College of Medicine, Iowa City, Iowa, USA; 3Oregon Health & Science University, Portland, Oregon, USA; 4Portland VA Medical Center, Portland, Oregon, USA; 5University of Arizona College of Public Health, and University of Arizona Cancer Center, Tucson, Arizona, USA; 6University of Iowa Carver College of Medicine, University of Iowa College of Public Health; and Holden Comprehensive Cancer Center, University of Iowa, Io

FAQs

What patient groups were evaluated for FIT accuracy in this surveillance setting?

Patients were categorized by previous colonoscopy findings into low-, intermediate-, or high-risk polyp groups, and analyses focused on those with nonadvanced prior lesions.

How did the study compare FIT cutoffs for detecting advanced colorectal neoplasia?

It compared an optimal quantitative cutoff identified by the Youden index against the standard cutoff of 100 ng/mL, using diagnostic performance metrics.

What did serial FIT testing contribute to cumulative detection?

Cumulative sensitivity across three rounds was higher at the optimal cutoff (73.4%) than at the standard cutoff (37.1%), while specificity decreased at the lower optimal cutoff.

Sep 23, 2026

Uploaded by Jordan Avery